Cancer is a major public health problem in the United States. According to the American Cancer Society, cancer causes one in four deaths in the United States. The most common form of cancer is skin cancer, which inflicts one in five Americans in their lifetime.
In some cases, skin cancer is curable if detected early and treated properly. Typically, detection is based on surgical biopsy in which a sample of the skin is excised from the patient and is dissected to check for cancerous cells. However, diagnosing skin cancer from an excised sample of skin may be disadvantageous. Because the sample excised is small and the dissection of the sample is random, a diagnosis based on biopsy may be inaccurate. If a cancer diagnosis is made, the patient may be required to return for further biopsies until the extent of the cancer is determined. Complications may also arise as a result of biopsy such as infection, hemorrhage, and the spreading of cancer cells.
An alternative method for diagnosing cancer may exploit non-invasive optical imaging techniques, such as optical coherence microscopy (OCM). OCM reconstructs an image of a cross-section of tissue from light that is reflected off of points located on or in the tissue. To ascertain the presence of cancerous cells, the image may be manually evaluated by a physician or electronically evaluated by a computer. For accurate diagnosis, it may be desirable for the image to have a relatively high resolution so that individual skin cells can be differentiated. It also may be desirable for the image to extend below the surface of skin, through the epidermis in which most skin cancers develop, and into a portion of the dermis into which most skin cancers spread. Because the imaged material is not removed from the patient, it may be desirable to image at a relatively high speed to minimize distortion associated with patient movement, such as breathing.